Jurgen Klopp’s side looked on course for a hard-fought victory at the AMEX stadium thanks to Diogo Jota’s second half strike but were pegged back after Andy Robertson fouled Danny Welbeck in the box in stoppage time, allowing Pascal Gross to tuck home the resulting spot kick.
Brighton’s equaliser came after referee Stuart Atwell consulted his pitch side monitor and Liverpool also had goals by Mohamed Salah and Sadio Mane ruled out by the technology for marginal offside decisions.
The Liverpool captain was seething after the game, insisting even his opponents felt the decision to award Brighton a second penalty after Neal Maupay missed another in the first half was wrong.
“It was ours. It should be three points, in my opinion,” Henderson told BT Sport.
“I’ve seen the replay. Who would be happy? It’s not a pen. It feels like we’re standing here every week and discussing incidents. I don’t want to get into trouble, but for me it’s not a penalty.
“Danny Welbeck said to me it wasn’t a penalty. There were four or five of them who felt it wasn’t a penalty.
“To overturn it, it has to be clear and obvious. Is that a clear and obvious penalty, to go to the screen and overturn it?
“Obviously the referees know better than us, but I thought the lads were brilliant today and deserve the three points.
“In the first half there were things we could improve on, in the second half we did that.
“We had a couple of goals ruled off for offside. Overall we’ve got to be positive and take the performance out of it, because the result isn’t anything else but an error in my option.
“You’d rather get beat by two or three than end up like that. It feels like two points taken away from us.”
Liverpool moved top of the table with a point but could surrender top position on Sunday if other results do not go their way.
